Breech-closing means for selfloading firearms



F. L. HUMESTON BREECH- Filed March '5, 1942 5 Sheets-Sheet l &

I IIIIIII.

April 17, 1945. F, L. HUMESTON 2,373,761

BREECH-CLOSING MEANS FOR SELF-LOADING FIREARMS Filed March 5, 1942 3 Sheets-Sheet 2 April 1945. F. HUMESTON 2,373,761

BREECH-CLOSING MEANS FOR SELF-LOADING FIREARMS Filed March 5, 1942 3Sheets-Sheet 3 Patented Apr. 17, 1945 BREECH-CLOSING llIEANS FOR SELF- LOADING FIREARMS Frederick L. Humeston, Hamden, Conn, assignor to Western Cartridge Company, New Haven, Conn, a corporation of Delaware Application March 5, 1942, Serial No. 433,450

v 6 Claims.

The present invention relates to improvements in breech-closing means for firearms, and relates more particularly to improvements in breech-closing springs for self-loading firearms,

i. e., firearms in which the forces developed by.

means for moving the breech-bolt thereof into its I breech-closing position following the retirement of the said breech-bolt as an incident to the discharge of a cartridge.

Another object of the present invention is to provide superior breech-closing spring-means for self-loading firearms which spring-means is effective without requiring the formation in the firearm structure of costly and time-consuming lengthy sockets to accommodate a breech-closing spring.

A further object of the present invention is to provide a self-loading firearm with superior breech-closing means which may be produced at a low cost for manufacture and which will withstand long periods of continued and hard usage.

Still another object of the present invention is to provide a self-loading firearm with superior breech-closing spring-means which may be. readily and conveniently assembled with and demounted from a firearm structure without requiring the use of special tools.

With the above and other objects in view, as will appear to those skilled in the art from the present disclosure, this invention includes all features in the said disclosure which are novel over the prior art and which are not claimed in any separate application.

In the accompanying drawings, in which certain modes of carrying out the present invention are shown for illustrative purposes:

Fig. 1 is a view in side elevation of a self-loading rifle or carbine embodying the present invention;

Fig. 2 is a broken view mainly in side elevation and partly in vertical central-longitudinal section of the receiver, action-slide, breech-closing spring-means and associated elements of the firearm;

Fig. 3 is a view thereof partly in bottom elevation andpartly in longitudinal section, taken on the line 3-3 of Fig. 2;

Fig. 4 is a view in rear elevation of the receiver and breech-closing means, but including also a portion of the stock;

Fig. 5 is a transverse sectional View taken on the line 55 of Fig. 2 and includingthe stock;

Fig. 6 is a broken view in side elevation of the rear portion of the receiver together with the rear portion of the spring-guiding tube;

Fig. 7 is a longitudinal sectional view taken on the line !'I of Fig. 6;

Fig. 8 is a broken sectionalized perspective view of the rear portion of the receiver, detached;

Fig. 9 is a perspective view of the tube-head, detached;

Fig. 10 is a broken perspective view of the rear portion of the spring-guiding tube prior to its being connected to the tube-head;

Fig. 11 is a transverse sectional view of the rear portion of the receiver and the breech-closing spring-means of an alternative form of the present invention and taken. on the line Il--ll of Fig. 12;

Fig. 12 is a broken longitudinal sectional View taken on the line l2-l 2 of Fig. 11;

Fig. 13 is a broken perspective view of the rear portion of the receiver of the structure of Figs. 11, 12 and 14;

Fig. 14 is a broken View in side elevation of the rear portion of the receiver of the structure of Figs. 11, 12 and 13,;

Fig. 15 is a broken perspective view ofthe rear portion of the spring-guiding tube shown in Figs. 11 and 12;

Fig. 16 is a transverse sectional View of the same general character as Fig. 11, taken on the line I6l6 of Fig. 17, and showing still another form of the present invention;

Fig. 17 is a broken vertical longitudinal sectional View taken on the line l'lll of Fig. 16; and

Fig. 13 is a broken perspective view of the rear portion of the spring-guiding tube of the structure of Figs. 16 and 17.

The structure of Figs. 1 to 10 inclusive The particular self-loading firearm structure illustrated in Figs. 1 to 10 inclusive of the accompanying drawings, includes, in the main, a stock 25, a receiver 26, a barrel 21, a barrel-cap 28 and a reciprocating action-slide 29. The receiver 26, barrel 21 and action-slide 29 are preferably formed of highgrade steel to afford maximum strength and minimum weight while the stock 25 and the barrel-cap 28 are preferably formed of wood or other suitable heat-insulating material.

The rear end of the barrel 2! is rigidly .conne cted inany suitable manner to the forward end of the receiver 26 which latter is formed interiorly with a mechanism-receiving chamber 30 accommodating various features of the firearm mechanism, not requiring detailed description herein other than to note that the mechanism includes a reciprocating breech-bolt 3| which also has oscillatory movement in the receiver in a manner broadly similar to the breech-bolt of the well-known Garand rifle.

The action-slide 29 above referred to is mounted for reciprocation in any approved manner, mainly adjacent the right side of the receiver 23 and the rear portion of the barrel 21, and includes a bar-like portion 32 extending longitudinally of the firearm structure and terminating at its rear in a laterally-extending operating-handle 33 and an upwardly-extendin cam-lug 34. At the forward end of the bar-like portion 32, the action-slide 29 terminate in a crosshead 35 normally located adjacent a lug 36 formed integral with and depending from the barrel 2'! a short distance forwardly of the front end of the receiver 26.

The upwardly-extending cam-lug 34 of the action-slide 29 is formed in its inner face with a cam-recess 31 receiving an operating-lug 38 (Fig. 2) forming a feature of the forward end of the breech-bolt 3| before referred to. The details of the connection of the action-slide 29 to the breech-bolt 3| to effect the retirement and ,advancement thereof, form per se no essential feature of the present invention and do not require detailed description herein, but are shown and described in detail in my co-pending application, Serial No. 411,783, filed September 22, 1941, now Patent No. 2,308,283, dated January 12, 1943.

The downwardly-extending integral lug 36 of the barrel 2'! is formed with a rearwardly-opening piston-chamber 39 having its longitudinal axis extending in substantial parallelism with the axis of the barrel 2'', as is shown particularly well in Fig. 2. Leading forwardly and upwardly from the front end of the said piston-chamber 39 is a gas-passage 40 communicating at its upper forward end with the bore 4! of the barrel 2! so a to conduct gas-pressure from the said bore to the piston-chamber 39 before referred to.

Reciprocating in the piston-chamber 39 in the lug 36 of the barrel 21 is a piston generally designated by the reference character 42 and including at its forward end a head 43 from which rearwardly projects an integral cylindrically-contoured stem 44 of sufficient length to normally extend beyond the rear face of the lug 36. The said stem 44 extends axially rearwardly through a retaining-ring 45 threaded into the rear end of the piston-chamber 39 and having its conically-contoured forward face engaged, on occasion, by the conically-contoured rear face of the head43 of the piston 42.

The rear face of the stem 44 0f the piston 42 above referred to normally engages with the forward face of the erosshead 35 of the action-slide 29 and the said piston serves, in a manner as will more fully hereinafter appear, to forcibly drive the action-slide 29 together with the breech-bolt 3i, rearwardly upon each discharge of the firearm.

The bar-like portion 32 normally reciprocates upon the upper surface of a longitudinally-extending and laterally-projecting rib 46 formed integral with the right side of the receiver 26, as is especially well shown in Fig. 5. Beneath the rib 46, the right side of the receiver 26 is milled out or otherwise shaped to provide a longitudinal groove 41 of substantially semicircular form in cross section. The said groove terminates at its rear at a lug-like seat 48 formed integral with the extreme rear portion of the right side of the receiver 26 and having its front face perpendicular to the longitudinal axis of the groove 41 just referred to. The said lug-like seat 48 is formed with an anchoring-bore or socket 4%) extending through the said seat from front to rear in axial alignment with the longitudinal axis of the groove 41 in the right side of the receiver 26.

The anchoring-bore 49 in the lug-like seat 48 of the receiver 26 receives with a free fit a cylindrically-contoured anchoring-stem 5D projecting rearwardly from a tube-head generally designated by the reference character 5i and shown especially well in Figs. '7 and 9. The said tubehead is rigidly attached to the rear end of a thinwalled spring-guiding tube or member 52 which is accommodated in the longitudinal groove 41 in the right side of the receiver 26. The tubehead 5| before referred to is formed intermediate its respective opposite ends with an annular stopfiange 53 having its rear face seated against the forward face'of the lug-like seat 48 of the receiver 26. tube-head 5| is formed with an annular coupling-groove 54 into which is spun or otherwise formed, an annular coupling-rib 55 forming an integral feature of the spring-guiding tube 52 and located just short of the extreme rear end thereof, as is shown especially well in Fig. '7. The interengageme'nt of the coupling-rib 55 and the walls of the annular coupling-groove 54 serve to interlock or couple the tube-head 5| to the tube 52 so as to form a unit therewith.

Extending into the interior of the spring-guiding tube'52 is the rear portion of a helical breechclosing spring 56 which, at its forward portion, encircles a breech-closing plunger 51. The said plunger 51 is formed at its forward end with a head 58 having its forward end fitting into a rearwardly-opening recess 59 in the rear face of the crosshead 35 of the action-slide 29. The forward end of the breech-closing spring 56 thrusts forwardly against the rear face of the head 58 of the breech-closing plunger 51, while the rear end of the said spring thrusts rearwardly against the forward face of the tube-head 5! and hence also thrusts rearwardly against the lug-like seat 49 of the receiver 26.

As thus constructed and arranged, the breechclosing spring 56 acting through the breech-closing plunger 51 exerts a constant but yielding effort to maintain the action-slide 29 and the breech-bolt 3| in their foremost positions, in which positions the said breech-bolt closes the breech of the gun in a manner Well,understood in the art.

When the firearm is discharged, pressure-from the bore 4! of the barrel 2! will be transmitted through the inclined gas-passage- 49 and will cause the piston 42 to rapidl move rearwardly until the rear face of its head 43 engages with the forward face of the retaining-ring 45. The described movement of the piston 42 will impart a rapid rearward movement to the actionslide 29 but due to its momentum, the said actionslide will continue rearwardly after the piston has ceased its rearward travel as above described. The rearward movement of the action-slide 29 Forwardly of its stop-flange 53, the

as just referred to will be accomplished against the tension of the breech-closing spring 56 and will move the breech-bolt 3| rearwardly to effect the extraction and ejection of the just-fired cartridge in any suitable manner not requiring detailed description herein.

When the action-slide moves rearwardly upon the discharge of the firearm as above described,-

the breech-closing plunger 51, together with the breech-closing spring 56, will telescope rearwardly into the spring-guiding tube 52 and upon the completion of the full rearward travel of the said action-slide 29 and the breech-bolt 3!, the breech-closing spring 56 will be enabled to assert itself and thus restore itself, the plunger 51,

action-slide 29, breech-bolt 3|, and parts con-.

nected thereto, to the positions in which they are shown in Figs. 2 and 3.

When it is desired to demount the breechclosing spring 55 and associated parts from the receiver 26 or other suitable feature of the firearm, the said receiver and the parts organized therewith are first detached or dismounted from the stock 25. The breech-closing plunger 51 may now be manually forced rearwardly until the forward end of its head 58 is freed of the recess 59 in the crosshead 35, whereupon the forward end of the said plunger 57 may be moved laterally to one side of the firearm and freed for forward movement. When the breech-closing plunger is released and swung laterally as just described, the spring-guiding tube may pivot, in the anchoring bore 49 to the slight degree required to freely permit the lateral movement referred to.

When the forward end of the breech-closing plunger 57 is clear of the crosshead 35, it may be pulled forwardly, together with the breechclosing spring 56, out of the open forward end of the spring-guiding tube 52 and demounted from the firearm structure. Either coincidentally with or subsequent to the described demounting movement of the plunger 51, the spring-guiding tube 52 may be moved forwardly so as to remove the anchoring-stem 50 to its tube-head from the anchoring-bore or socket 49, whereupon the said tube and its said head is free for removal from the receiver.

The spring-guiding tube 52, spring 55 and Plunger 5? may be reassembled with the firearm structure in several different manners, but it is convenient to first manipulate the spring-guiding tube 52 so as to enter the anchoring-stem 50 of its tube-head 5! into the anchoring-bore 49 of the receiver. Having performed this step and while the forward end of the tube 52 is still displaced outwardly with respect to the groove 4'! in the receiver, the breech-closing spring 56 and the breech-closing plunger 51 may be inserted into the open forward end of the said tube 52. Now by manually forcing the breech-closing plunger '51 rearwardly to a degree suflicient to permit its forward end to clear or slide along the rear face of the crosshead 35 of the actionslide 29. the entire breech-closing spring-means, comprising in th instance shown, the parts 5!, 52, 56 and 51, may be swung about the anchoring-stem 50 as a fulcrum. When the head '58 of the plunger 5'! is aligned with the recess 59 in the cross-head 35, the said head may be released to the action of the spring 56 to seat itself in the said recess 58, whereupon the spring-closing means is ready for operation in its normal manner.

The forward end of the spring-guiding tube 52 may be retained against outward swinging movement in any suitable manner, such for instance as by the adjacent portion of the stock 25 (Fig. 5) or by the normal entry of an appreciable portion of the rear end of the breech-closing plunger 5! into the said tube.

The structure of Figs. 11 to 15 inclusive The form of the invention shown in Figs. 11 to 15 inclusive, has the same general basic characteristics as that shown in the preceding figures and differs therefrom in details as will be presently described.

For purposes of convenience, the receiver of the structure now being described will be designated by the same reference character as the receiver 25 save for the addition of the reference charac ter (1. Thus, the receiver of the structure of Figs. 11 to 15 inclusive is designated as 26a and similarly, corresponding parts generally corresponding to the structure of Figs. 1 to 10 inclusive will, wl'rere suitable, bear like reference characters plus the reference character a.

The receiver 251; of the structure now being described, has its longitudinal groove 47a extended completely to the rear face of the receiver and has no lug-like seat 48. At the rear of its said longitudinal groove 41a, the receiver 26a is formed with a keyhole-shaped opening leading inwa rdly into an undercut socket 6| located mainly to the rear of the large forward portion of the keyhole-shaped opening 50. Normally seated in the socket 6| is the comically-contoured head 62 at the inner end of an anchoring-stud 53. The said anchoring-stud 53 extends transversely through and is riveted in the rear portion of a spring-guiding tube 52a extending longitudinally in the longitudinal groove 47a of the receiver 26a in a manner generally similar to the relationship of the tube 52 and receiver 26 of the structure of Figs. 1 to 10 inclusive. The fit of the head 62 of the anchoring-stud 63. in the socket BI, is preferably sufiiciently free to permit the forward portion of the tube 52a to be swung laterally away from the adjacent portion of the receiver 26a.

The spring-guiding tube 52a is rolled. up from sheet metal and throughout the major portion of its length. it is of cylindrical form save at its rear where the metal is shaped to constitute in cross section a substantiall rectangular figure, as is especially well shown in Fig. 15. The anchoring-stud 53 thus extends transversely through two laterally-spaced-apart ears B4l i at the rear of the tube 52a are respectively bent downwardly and upwardly at a point slightly forwardly of the anchoring-stud 53 to provide a rear-end wall against the forward face of which is seated the rear end of a helical breechclosing spring 55a, as is shown in Fig. 12.

The breech-closing spring 55a just above re fer-red to may correspond to the breech-closing spring 56 of the structure of Figs. 1 to 10 inclusive, and its tension serves to maintain the conically-contoured head 62 of the'anchoring-stud 53 in the conically-contoured undercut socket Bl in the receiver 26a. The spring-guiding tube 52a may be detached from the receiver 26a by moving it forwardly from the position in which it is shown in Fig. 12 until the head 62 of its anchoring-stud 6-3 is in,registry with the large forward portion of the keyhole-shaped opening 60, whereupon the rear end of the tube 52a may be moved laterally away from the receiver 25a to completely separate the anchoring-stud 63 from the socket 6i The structure of Figs. 16, 17 and 18 In this structure and where suitable, parts generally corresponding to the parts shown in Figs. 1 to inclusive will bear similar reference characters save for the addition of the reference character b.

In the structure now being described, the receiver 2% generally corresponds to the receivers 28 and 26a before described, and is formed beneath its laterally-extending longitudinal rib 4% with a longitudinal groove 41?) opening downwardly and to the right and of substantiall semicircular form in cross section. Accommodated in the longitudinal groove lib in the receiver 261? is a spring-guiding tube 521) which may be conveniently rolled up from sheet metal.

Just short of its rear, the under portion of the tube 422) is deflected upwardly to provide a rear-end wall 85 providing a seat for the rear end of a helical breech-closing spring 5622 corresponding in function to the function of the breech-closing springs 56 and 56a before described. The creation of the rear-end wall 68 on the tube 52b leaves the upper wall portion of the tube extending rearwardly to constitute 001'11- plemental anchoring-fingers 61-61 laterally spaced from each other by a notch 68, as is shown especially well in Fig. 18.

The anchoring-fingers 61-61 of the tube 52b straddle the shank of an anehoringstud 69 just above the head In thereof, as is shown especially well in Fig. 16. The said anchoring-stud is mounted in the rear portion of the laterally-projecting longitudinal rib 46b of the receiver 261) in such manner as to have the upper surface of the head 19 at the lower end of the said anchoring-stud, in spaced relationship below the under surface of the said rib.

As thus constructed and arranged, the tension of the breech-closing spring 56b serves to maintain the anchoring-fingers 61- 3! of the tube 52b in position to embrace the anchoring-stud $9, to thus releasably attach the said tube to the receiver with capacity for having its forward end rocked away from the receiver to a slight degree in a manner generall like that described in connection with the tube 52.

Resume In all of the forms of the invention herein shown and described, not only is the demounting of the breech-closing spring facilitated, but the structure is more economical to produce, since it does not require the accurate drilling of a long longitudinal recess directly in the metal of the side of the receiver, in order to provide guideand housing-means for the rear portion of a breech-closing spring.

The invention may be carried out in other specific ways than those herein set forth without departing from the spirit and essential characteristics of the invention, and the present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, and all changes coming within the meaning and equivalency range of the appended claims are intended to be embraced therein.

I claim:

1. A firearm structure including in combination: a receiver; a breech-bolt movable in the said receiver; an action-slide movable adjacent the said receiver and operatively connected to the said breech-bolt; a stock having a recess therein accommodating the said receiver; and breechclosing spring-means comprising a normally-stationary spring-guiding tube formed independently of and located exteriorly of the said receiver in a position intermediate the outer surface there of and the adjacent inner surface of the recess in the said stock, the said tube having an open forward end, a breech-closing plunger telescopically fitting within the open forward end of the said spring-guiding tube and having its forward end extending forwardl therefrom into engagement with a portion of the said action-slide, and a helical breech-closing spring compressible and extensible axially in the said spring-guiding tube and freely removable through the open forward end thereof, the said spring telescopically fitting over the said breech-closing plunger and thrusting forwardly against the latter to yieldingly urge the said breech-bolt intoits breech-closing position.

2. A firearm structure including in combination: a receiver; a breech-bolt movable in the said receiver; an action-slide movable adjacent the said receiver and operatively connected to the said breech-bolt; a stock having a recess therein accommodating the said receiver; breech-closing spring-means com-prising a normally-stationary spring-guiding tube formed independently of and located exteriorly of the said receiver in a position intermediate the outer surface thereof and the adjacent inner surface of the recess in the said stock, the said tube having an open forward end, a breech-closing plunger telescopically fitting within the open forward end of the said spring-guiding tube and having its forward end extending forwardly therefrom into engagement with a portion of the action-slide, and a helical breech-closing spring compressible and extensible axially in the said spring-guiding tube and freely removable through the open forward end thereof, the said spring telescopically fitting over the said breech-closing plunger and thrusting forwardly against the latter to yieldingly urge the said breech-bolt into its breechclosing position; and releasable anchoring means constructed and arranged to releasably hold the .rear portion of the spring-guiding tube of the said breech-closing spring-means to the receiver with capacity for lateral swinging movement of the said tube with respect thereto.

3. A firearm structure including in combination: a receiver formed in an outer face thereof with a longitudinal laterally-open groove; a breechbolt movable in the said receiver; an action-slide movable adjacent the said receiver and operatively connected to the said breech-bolt; a stock having a recess therein accommodating the said receiver; and breech-closing spring-means comprising a normally-stationar spring-guiding tube formed independently of the said receiver and seated in the longitudinal groove therein in a position interiorly of the adjacent inner surface of the recess in the said stock, the said tube having an open forward end, and a helical breech-closing spring compressible and extensible axially in the said spring-guiding tube and freely removable through the open forward end thereof, the said spring thrusting forwardly against the said action-slide to yieldingly urge the said breech-bolt into its breech-closing position.

4. A firearm structure including in combination: a receiver formed in an outer face thereof with a longitudinal laterally-open groove; a breech-bolt movable in the said receiver; an action-slide movable adjacent the said receiver and operatively connected to the said breech-bolt; a stock having a recess therein accommodating the position interiorly of the adjacent inner surface of the recess in the said stock, the said tube having an open forward end, and a helical breechclosing spring compressible and extensible axially in the said spring-guiding tube and freely removable through the open forward end thereof, the said spring thrusting forwardly against the said action-slide to yieldingly urge the said breechbolt into its breech-closing position; and releasable anchoring-means located adjacent the rear of the longitudinal groove in the said receiver and constructed and arranged to hold the rear portion of the spring-guiding tube of the said breech-closing spring-means in the groove of the said receiver with capacity for lateral swinging movement of the said tube with respect thereto. I

5. A firearm structure including in combination: a receiver provided on its outer face with a laterally-extending longitudinal rib and formed beneath the said rib with a downwardly and laterally-opening longitudinal groove; a breech-bolt movable in the said receiver; an action-slide movable adjacent the said receiver and operatively connected to the said breech-bolt; a stock having an upwardly-opening recess therein accommodating the said receiver; a normallystationary spring-guiding tube located in the groove in the said receiver and having an open forward end and lying in a position intermediate the said receiver and the adjacent inner surface of the recess in the said stock,- and a helical breech-closing spring having a rear portion compressible and extensible axially in the said springguiding tube and freely removable through the open forward end thereof, the said spring thrusting forwardly against the said action-slide to yieldingly urge the said breech-bolt into its breech-closing position.

6. A firearm structure includingin combination: a receiver provided on its outer face with a laterally-extending longitudinal rib and formed beneath the said rib with a downwardly and laterally-opening longitudinal groove; a breechbolt movable in the said receiver; an actionslide movable adjacent the said receiver and operatively connected to the said breech-bolt; a stock having an upwardly-opening recess therein accommodating the said receiver; a normally-stationary spring-guiding tube located in the groove in the said receiver and having an open forward end and lying in a position intermediate the said receiver and the adjacent inner surface of the recess in the said stock; a helical breech-closing spring having a rear portion compressible and extensible axially in the said spring-guiding tube and freely removable through the open forward end thereof; and a breech-closing spring-plunger extending within the open forward end of the said tube and axially in telescopic engagement with the said breech-closing spring and yieldingly urged thereby in a direction forwardly of the firearm structure to, in turn, yieldingly urge the said breech-bolt into its breech-closing position.

FREDERICK L. HUMES'I'ON. 

